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5.2 Installation on Steel or Concrete Surfaces using Epoxy Cements.
Geokon strain gages can be epoxied to steel or concrete surfaces if proper care is taken to
clean the surfaces to be bonded and if sufficient time is allowed for the epoxy to cure before
the gages are attached to the mounting blocks.
5.2.1 Concrete Surfaces:
Materials
Devcon Underwater Putty P/N 11800
Loctite 410 Instant Adhesive P/N 41045
1. Mix a small quantity of the two part underwater epoxy. The ratio is 1/1
2. Grind and/or sand the surfaces to be bonded, (this includes both the concrete and
the end block surfaces), and then clean with compressed air or aerosol cleaner.
3. Attach the mounting blocks to the spacer jig, as per section 2.2 above.
4. Apply a thin layer of the premixed underwater epoxy to the center 2/3 rds of the
mounting block, (see sketch below).
5. Apply a thin layer of 410 Instant adhesive to the outside edges of the mounting
blocks.
6. Press the assembly firmly against the surface and hold in place for 2 minutes.
7. Carefully remove the spacer bar from the mounting blocks.
8. Allow 24 hours curing time before the gages are installed.
Figure 8 Installation using Epoxy
5.2.2 Steel Surfaces:
Use Loctite Speedbonder H4500. This can be purchased in Cartridge form that
automatically dispenses the two-part adhesive in its correct 10/1 mixture. The adhesive sets
up to maximum strength in 10 minutes during which time the mounting blocks should be
held to the surface using hand pressure, weights or magnets.
Loctite 410
Devcon Underwater Putty
